Effect and mechanism of connective tissue growth factor on myocardium fibrosis of renal hypertensive rat

Abstract

Objective To investigate the roles of CTGF in the development of myocardial fibrosis of renovascular hypertensive rats from molecular level. Methods Renovascular hypertensive rat ( RHR ) animal models were constructed. Sham operational rats were used as control group. CTGF, TGF-β1were evaluated by qualitative and semiquantitative immunohistoehemical staining in the sixth and the twelfth week after operation to explore their distribution and expression in left ventrieular tissue. CTGF mRNA, TGF-β1 mRNA were evaluated by RT-PCR, and the total collagen in left ventrieular interstitial tissue were observed, CVF, PIP and Coll were also measured. Results Compared with sham operated rat, CVF, PIP and Coll carboxypropetide of precollagen Ⅰ and collagen concentration in renovaseular hypertensive rat were higher(P<0.01). The expression of CTGF, TGF-β1 and CTGF mRNA, TGFβ1 mRNA in myocardium of left ventricle of RHR were higher than those in SOR, CTGF primarily reacted with myocardial interstitium and artery. TGF-β1 mainly expressed in myocardial cells. The expression of CTGF,TGF-β1 and CTGF mRNA, TGFβ1mRNA in myocarclium of left ventricle of the twelfth week RHR or SHR were higher than that in the sixth RHR or SHR( P <0. 05). Correlative analysis revealed that CTGF was positively correlated with ( r =0.815, P < 0.01) ,TGF-β1 ( r = 0. 626, P < 0. 05 ), CVF( r = 0. 742, P < 0. 01 ), Coll ( r = O. 793, P < 0. 01 ) and PICP( r = 0. 675, P <0. 01 ). Conclusions CTGF may play an important role in the development of myocardial interstitial fibrosis. Key words: Intercellular signaling peptides and proteins/PD ; Hypertension; renaL/DT; Endomyocardial fibrosis/DT